From patchwork Thu Sep 28 10:18:53 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sudeep Holla X-Patchwork-Id: 114403 Delivered-To: patch@linaro.org Received: by 10.140.106.117 with SMTP id d108csp555408qgf; Thu, 28 Sep 2017 03:19:12 -0700 (PDT) X-Google-Smtp-Source: AOwi7QC00dBXjHmAqJGGro981CHBsnD1ML/HsUJhKhykhqS7PtRDzJ4VGyYtkMwK+qYHi8CmnBb4 X-Received: by 10.159.245.146 with SMTP id a18mr3630260pls.26.1506593952683; Thu, 28 Sep 2017 03:19:12 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1506593952; cv=none; d=google.com; s=arc-20160816; b=HeTn40MHzh3lT94scCLqVqwGMNnCWZi0Ul5cgV0fzQriOWMlGAl+VOVIXKuAnAF6im 8C0juCclnCpLl5JRZoiwLiWMAxExAoOJl1ZelppvrWuNLYIq4Khag9J1an0uPbkbyfPH YyAMbgzTG0X/Bjzr2uMkKYcaO7TMEwAwtawRUUrBTe+G8iiKFQ1489kt/tt0a2U0dy5B El4F0EnVENDt764KslxzFnHQ1lb7/9KuRfuulZYJaQcCdYpaIH5whDTwlBDIOKDvQ67M OpmczXUWynsC6cpcxOaA09JfzC71Sn6gwVsNRzGLM/0F0kqmQ+efdGI0Gb2p+Q9bSMjA WMdQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:arc-authentication-results; bh=6xcLOzGrPxuVYIoG5MV0HsW0lnKwcmfuMbBtvDKQnzA=; b=z0MmhIphceu09yqW+rE74WUCkrWCTTHyZhV7c3FlMxz2liAysPajHONvGsOLw4Pj4t c7hC9cBqq3R7MccKHMYDcE+H6O9AkEliAiugAspz8Zm36TZlPAX+DqVzbSRjdSqm2gg9 A+Ve9DOrb3aiVEehk0FqDdcI64LTXZ9kgPu3IIKzWItVNwpC5WYCxu/4CFRLilLaDlBR wV+rie5H30rz1YgjrUrkxIXNqGdAXXM46ofP5dfrY/J3RNbbcGQ7s/6Q/vMvDVgSJSMt JSQsOevH+35p//264xxwL5fPUPbIKNm1/ib1ZRowc9g/y60gR5YJUA3ge2qj9WA2qIhr crPw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id 77si1109447pfz.364.2017.09.28.03.19.12; Thu, 28 Sep 2017 03:19:12 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752817AbdI1KTK (ORCPT + 26 others); Thu, 28 Sep 2017 06:19:10 -0400 Received: from foss.arm.com ([217.140.101.70]:54650 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752688AbdI1KTF (ORCPT ); Thu, 28 Sep 2017 06:19:05 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 9E2841529; Thu, 28 Sep 2017 03:19:05 -0700 (PDT) Received: from e107155-lin.cambridge.arm.com (unknown [10.1.210.28]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B36253F3E1; Thu, 28 Sep 2017 03:19:04 -0700 (PDT) From: Sudeep Holla To: linux-kernel@vger.kernel.org, Jassi Brar Cc: Sudeep Holla , Jassi Brar Subject: [RESEND][PATCH 2/2] mailbox: mailbox-test: don't rely on rx_buffer content to signal data ready Date: Thu, 28 Sep 2017 11:18:53 +0100 Message-Id: <1506593933-5857-2-git-send-email-sudeep.holla@arm.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1506593933-5857-1-git-send-email-sudeep.holla@arm.com> References: <1506593933-5857-1-git-send-email-sudeep.holla@arm.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently we rely on the first byte of the Rx buffer to check if there's any data available to be read. If the first byte of the received buffer is zero (i.e. null character), then we fail to signal that data is available even when it's available. Instead introduce a boolean variable to track the data availability and update it in the channel receive callback as ready and clear it when the data is read. Cc: Jassi Brar Fixes: baef9a35d246 ("mailbox: mailbox-test: add support for fasync/poll") Signed-off-by: Sudeep Holla --- drivers/mailbox/mailbox-test.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) -- 2.7.4 diff --git a/drivers/mailbox/mailbox-test.c b/drivers/mailbox/mailbox-test.c index 97fb956bb6e0..93f3d4d61fa7 100644 --- a/drivers/mailbox/mailbox-test.c +++ b/drivers/mailbox/mailbox-test.c @@ -30,6 +30,7 @@ #define MBOX_HEXDUMP_MAX_LEN (MBOX_HEXDUMP_LINE_LEN * \ (MBOX_MAX_MSG_LEN / MBOX_BYTES_PER_LINE)) +static bool mbox_data_ready; static struct dentry *root_debugfs_dir; struct mbox_test_device { @@ -152,16 +153,14 @@ static ssize_t mbox_test_message_write(struct file *filp, static bool mbox_test_message_data_ready(struct mbox_test_device *tdev) { - unsigned char data; + bool data_ready; unsigned long flags; spin_lock_irqsave(&tdev->lock, flags); - data = tdev->rx_buffer[0]; + data_ready = mbox_data_ready; spin_unlock_irqrestore(&tdev->lock, flags); - if (data != '\0') - return true; - return false; + return data_ready; } static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf, @@ -223,6 +222,7 @@ static ssize_t mbox_test_message_read(struct file *filp, char __user *userbuf, *(touser + l) = '\0'; memset(tdev->rx_buffer, 0, MBOX_MAX_MSG_LEN); + mbox_data_ready = false; spin_unlock_irqrestore(&tdev->lock, flags); @@ -292,6 +292,7 @@ static void mbox_test_receive_message(struct mbox_client *client, void *message) message, MBOX_MAX_MSG_LEN); memcpy(tdev->rx_buffer, message, MBOX_MAX_MSG_LEN); } + mbox_data_ready = true; spin_unlock_irqrestore(&tdev->lock, flags); wake_up_interruptible(&tdev->waitq);